FIG. 1.
Comparison of uncloned DENV2 strains PL046 and D2S10 with recombinant viruses derived from pPL046-IC (PL046-IC) and pE124/128-IC (E124/128-IC). (A) Plaque assays using BHK-21 cells were performed. Plaques were visualized day 5 p.i. for PL046 and PL046-IC and day 7 p.i. for D2S10 and E124/128-IC. (B) Virus was quantified by real-time RT-PCR in five different uncloned and four different recombinant preparations. The same preparations were used for plaque assay on BHK-21 cells to calculate viral RNA copies per PFU. The data represent means ± the standard errors of the mean (SEM). The asterisk indicates a difference that is statistically significant (P < 0.05). (C) Western blot of uncloned PL046 and D2S10 and recombinant viruses derived from pPL046-IC and pE124/128-IC. A monoclonal antibody (clone E18) was used to detect the E protein in 105 PFU of PL046 (lane 1), D2S10 (lane 2), PL046-IC (lane 3), and E124/128-IC (lane 4) and 104 PFU of PL046 (lane 5), D2S10 (lane 6), PL046-IC (lane 7), and E124/128-IC (lane 8). In this denaturing gel, the E monomer is detected as the major band of approximately 55 kDa.